Method for removing sulfate radical from lead sulfate alkaline electrolyte

Abstract

The invention discloses a method for removing sulfate radical from lead sulfate alkaline electrolyte. The method comprises the following steps: removing sulfate radical SO4<2-> from alkaline waste electrolyte with barium hydroxide Ba(OH)2 or barium oxide BaO, and thus sodium hydroxide NaOH is regenerated, and barium sulfate BaSO4 is also obtained and lead in lead waste electrolyte is not lost in a barium sulfate BaSO4 sediment; adding barium hydroxide Ba(OH)2 or barium oxide BaO according to the amount of Ba(OH)2 / SO4<2-> being 1 to 1.1 or Ba(OH)2 / Pb being 0.5 to 1, wherein the operation temperature is 80-900 DEG C and the time is 3-4 hours; heating the generated white sediment with clear water to 40-600 DEG C according to the liquid-to-solid ratio being 2-5, washing for 2-3 times, drying the obtained white solid, so as to form amorphous barium sulfate BaSO4, returning the lead waste electrolyte from which SO4<2-> is removed and extracting lead sulfate PbSO4. The sulfate radical SO4<2-> is removed from the alkaline lead waste electrolyte with barium hydroxide Ba(OH)2 or barium oxide BaO; meanwhile, NaOH is regenerated, and thus the high-quality barium sulfate BaSO4 product is obtained.

Description

technical field

[0001] The invention belongs to the field of hydrometallurgy, in particular to a method for removing sulfate radicals from lead sulfate alkaline electrolyte. Background technique

[0002] Lead Sulfate PbSO 4 The slag is leached with sodium hydroxide NaOH to obtain sodium plumbate Na 2 PbO 2 and sodium sulfate Na 2 SO 4 , Sodium hydroxide NaOH is regenerated after the electrolysis of metallic lead, but a considerable part of the sodium ion Na + Na 2 SO 4 The form is occupied and cannot be converted to sodium hydroxide NaOH. During electrolyte circulation, sodium sulfate Na 2 SO 4 Continuous enrichment, on the one hand, lead sulfate PbSO 4 The leaching rate decreases, and on the other hand, a large amount of sodium sulfate Na 2 SO 4 Crystallization, blocking the pipeline, so that the production can not be carried out smoothly. In order to make the sulfate ion SO 4 2- Open circuit, part of the electrolytic waste liquid was used to open the circuit...